List of elements by symbol

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Contents

This is a list of chemical elements by symbol, including the current symbols used to identify the chemical elements as recognized by the International Union of Pure and Applied Chemistry, as well as proposed and historical symbols. Also given is each element's atomic number, atomic mass or most stable isotope, group and period numbers on the periodic table, and origin of the symbol if not obvious from the current name of the element.

Chemical series of the periodic table
Alkali metals Alkaline earth metals Lanthanides Actinides Transition metals
Poor metals Metalloids Nonmetals Halogens Noble gases

[edit] Current symbols

Symbol Name Origin of Symbol Atomic Number Relative Atomic Mass Group Period
Ac Actinium corruption of the Greek aktinos 89 [227][1]   7
Ag Silver Latin argentum 47 107.8682(2)[2] 11 5
Al Aluminium (Aluminum) Latin alumen 13 26.9815386(8) 13 3
Am Americium the Americas 95 [243][1]   7
Ar Argon Greek argon 18 39.948(1)[2] [3] 18 3
As Arsenic Greek arsenikos 33 74.92160(2) 15 4
At Astatine Greek astatos 85 [210][1] 17 6
Au Gold Latin aurum 79 196.966569(4) 11 6
B Boron borax 5 10.811(7)[2] [4] [3] 13 2
Ba Barium Greek barys 56 137.327(7) 2 6
Be Beryllium beryl 4 9.012182(3) 2 2
Bh Bohrium Neils Bohr 107 [264][1] 7 7
Bi Bismuth corruption of the German wissmuth 83 208.98040(1) 15 6
Bk Berkelium Berkeley, California 97 [247][1]   7
Br Bromine Greek bromos 35 79.904(1) 17 4
C Carbon Latin carbo 6 12.0107(8)[2] [3] 14 2
Ca Calcium Latin calx 20 40.078(4)[2] 2 4
Cd Cadmium corruption of the Greek kadmia 48 112.411(8)[2] 12 5
Ce Cerium Ceres 58 140.116(1)[2]   6
Cf Californium State and University of California 98 [251][1]   7
Cl Chlorine Greek chloros 17 35.453(2)[2] [4] [3] 17 3
Cm Curium Pierre and Marie Curie and the traditional -um ending 96 [247][1]   7
Co Cobalt corruption of the German kobold 27 58.933195(5) 9 4
Cr Chromium Greek chroma 24 51.9961(6) 6 4
Cs Caesium (Cesium) Latin caesius 55 132.9054519(2) 1 6
Cu Copper Latin Cuprum 29 63.546(3)[3] 11 4
Db Dubnium Dubna, Russia 105 [262][1] 5 7
Ds Darmstadtium Darmstadt, Germany 110 [271][1] 10 7
Dy Dysprosium Greek dysprositos 66 162.500(1)[2]   6
Er Erbium Ytterby, Sweden 68 167.259(3)[2]   6
Es Einsteinium Albert Einstein 99 [252][1]   7
Eu Europium Europe 63 151.964(1)[2]   6
F Fluorine Latin fluo 9 18.9984032(5) 17 2
Fe Iron Latin ferrum 26 55.845(2) 8 4
Fm Fermium Enrico Fermi 100 [257][1]   7
Fr Francium France 87 [223][1] 1 7
Ga Gallium Latin Gallia 31 69.723(1) 13 4
Gd Gadolinium gadolinite 64 157.25(3)[2]   6
Ge Germanium Germany 32 72.64(1) 14 4
H Hydrogen Greek hydror 1 1.00794(7)[2] [4] [3] 1 1
He Helium Greek helios 2 4.002602(2)[2] [3] 18 1
Hf Hafnium Latin Hafnia 72 178.49(2) 4 6
Hg Mercury Latin hydrargyrum 80 200.59(2) 12 6
Ho Holmium Latin Holmia 67 164.930 32(2)   6
Hs Hassium Hesse, Germany 108 [277][1] 8 7
I Iodine Greek ioeides 53 126.904 47(3) 17 5
In Indium indigo blue 49 114.818(3) 13 5
Ir Iridium Greek iris 77 192.217(3) 9 6
K Potassium (Kalium) Latin kalium 19 39.0983(1) 1 4
Kr Krypton Greek kryptos 36 83.798(2)[2] [4] 18 4
La Lanthanum Greek lanthanien 57 138.90547(7)[2]   6
Li Lithium Greek lithos 3 6.941(2)[2] [4] [3] [5] 1 2
Lr Lawrencium Ernest O. Lawrence 103 [262][1] 3 7
Lu Lutetium Latin Lutetia 71 174.967(1)[2] 3 6
Md Mendelevium Dmitri Mendeleyev 101 [258][1]   7
Mg Magnesium Magnesia, Greece 12 24.3050(6) 2 3
Mn Manganese Latin magnes 25 54.938045(5) 7 4
Mo Molybdenum Greek molybdos 42 95.94(2)[2] 6 5
Mt Meitnerium Lise Meitner 109 [268][1] 9 7
N Nitrogen Greek nitron 7 14.0067(2)[2] [3] 15 2
Na Sodium Latin natrium 11 22.98976928(2) 1 3
Nb Niobium Niobe 41 92.906 38(2) 5 5
Nd Neodymium Greek neos didymos 60 144.242(3)[2]   6
Ne Neon Greek neos 10 20.1797(6)[2] [4] 18 2
Ni Nickel German kupfernickel 28 58.6934(2) 10 4
No Nobelium Alfred Nobel 102 [259][1]   7
Np Neptunium Neptune 93 [237][1]   7
O Oxygen Greek oxys 8 15.9994(3)[2] [3] 16 2
Os Osmium Greek osme 76 190.23(3)[2] 8 6
P Phosphorus Greek phosphoros 15 30.973762(2) 15 3
Pa Protactinium Greek protos and actinium 91 231.03588(2)[1]   7
Pb Lead Latin plumbum 82 207.2(1)[2] [3] 14 6
Pd Palladium Pallas and the traditional -dium ending 46 106.42(1)[2] 10 5
Pm Promethium Prometheus 61 [145][1]   6
Po Polonium Poland 84 [210][1] 16 6
Pr Praseodymium Greek prasios 59 140.90765(2)   6
Pt Platinum Greek platina 78 195.084(9) 10 6
Pu Plutonium Pluto 94 [244][1]   7
Ra Radium Latin radius 88 [226][1] 2 7
Rb Rubidium Latin rubidus 37 85.4678(3)[2] 1 5
Re Rhenium German Rheinprovinz 75 186.207(1) 7 6
Rf Rutherfordium Ernest Rutherford 104 261[1] 4 7
Rg Roentgenium Wilhelm Conrad Röntgen 111 [272][1] 11 7
Rh Rhodium Greek rhodon 45 102.905 50(2) 9 5
Rn Radon radium and emanation 86 [220][1] 18 6
Ru Ruthenium Latin Ruthenia 44 101.07(2)[2] 8 5
S Sulfur (Sulphur) Latin sulfur 16 32.065(5)[2] [3] 16 3
Sb Antimony Latin stibium 51 121.760(1)[2] 15 5
Sc Scandium Scandinavia 21 44.955912(6) 3 4
Se Selenium Greek selene 34 78.96(3)[3] 16 4
Sg Seaborgium Glenn T. Seaborg 106 [266][1] 6 7
Si Silicon Latin silex 14 28.0855(3)[3] 14 3
Sm Samarium samarskite 62 150.36(2)[2]   6
Sn Tin Latin stannum 50 118.710(7)[2] 14 5
Sr Strontium Latin Strontian 38 87.62(1)[2] [3] 2 5
Ta Tantalum King Tantalus 73 180.94788(2) 5 6
Tb Terbium Ytterby, Sweden 65 158.92535(2)   6
Tc Technetium Greek technetos 43 [98][1] 7 5
Te Tellurium Greek tellus 52 127.60(3)[2] 16 5
Th Thorium Thor 90 232.03806(2)[1] [2]   7
Ti Titanium the Titans 22 47.867(1) 4 4
Tl Thallium Greek thallos 81 204.3833(2) 13 6
Tm Thulium Thule and the traditional -ium ending 69 168.93421(2)   6
U Uranium Uranus 92 238.02891(3)[1] [2] [4]   7
Uub Ununbium Latin uni and bi 112 [285][1] 12 7
Uuh Ununhexium Latin uni and Greek hex 116 [292][1] 16 7
Uuo Ununoctium Latin uni and oct 118 [294][1] 18 7
Uup Ununpentium Latin uni and Greek pent 115 [288][1] 15 7
Uuq Ununquadium Latin uni and quadr 114 [289][1] 14 7
Uut Ununtrium Latin uni and Greek tri 113 [284][1] 13 7
V Vanadium Vanadis 23 50.9415(1) 5 4
W Tungsten German wolfram 74 183.84(1) 6 6
Xe Xenon Greek xenos 54 131.293(6)[2] [4] 18 5
Y Yttrium Ytterby, Sweden 39 88.90585(2) 3 5
Yb Ytterbium Ytterby, Sweden 70 173.04(3)[2]   6
Zn Zinc German zin 30 65.409(4) 12 4
Zr Zirconium zircon 40 91.224(2)[2] 4 5
Chemical series of the periodic table
Alkali metals Alkaline earth metals Lanthanides Actinides Transition metals
Poor metals Metalloids Nonmetals Halogens Noble gases

[edit] Symbols not currently used

The following is a list of names formerly used or suggested for use in naming the elements listed above. Also included in this list are placeholder names and names given by discredited claimants for discovery. Names which retain local use (as with aluminum and jod) are not included in this table.

Chemical Symbol Name Atomic Number Origin of Symbol Why Not Used
A Argon 18 Current symbol is Ar. [6]
Ab Alabamine 85 Discredited claim to discovery of astatine. [7]
Am Alabamium 85 Discredited claim to discovery of astatine. [7]
An Athenium 99 Proposed name for einsteinium. [8]
Ao Ausonium 93 Discredited claim to discovery of neptunium. [7]
Az Azote 7 Former name for nitrogen. [6]
Bv Brevium 91 Former name for protactinium. [6]
Bz Berzelium 59 Suggested name for praseodymium. [8]
Cb Columbium 41 Former name of niobium. [6]
Cb Columbium 95 Suggested name for americium. [8]
Cp Cassiopeium 71 Former name for lutetium. [6]
Ct Centurium 100 Proposed name for fermium. [8]
Ct Celtium 72 Former name of hafnium. [6]
Da Danubium 43 Suggested name for technetium. [8]
Db Dubnium 104 Proposed name for rutherfordium. The symbol and name were used for element 105. [6] [8]
Eb Ekaboron 21 Name given by Mendeleev to an as of then undiscovered element. When discovered, scandium closely matched the prediction. [8] [9]
El Ekaaluminium 31 Name given by Mendeleev to an as of then undiscovered element. When discovered, gallium closely matched the prediction. [8] [9]
Em Emanation 86 Also called radium emanation, the name was originally given by Friedrich Ernst Dorn in 1900. In 1923, this element officially became radon (the name given at one time to 222Rn, an isotope identified in the decay chain of radium). [6]
Em Ekamangan 43 Name given by Mendeleev to an as of then undiscovered element. When discovered, technetium closely matched the prediction. [8] [9]
Es Ekasilicon 32 Name given by Mendeleev to an as of then undiscovered element. When discovered, germanium closely matched the prediction. [8] [9]
Es Esperium 94 Discredited claim to discovery of plutonium. [7]
Fa Francium 87 Current symbol is Fr. [6]
Fr Florentium 61 Discredited claim to discovery of promethium. [7]
Gl Glucinium 4 Former name of beryllium. [6]
Ha Hahnium 105 Proposed name for dubnium. [8]
Ha Hahnium 108 Proposed name for hassium. [8]
Il Illinium 61 Discredited claim to discovery of promethium. [7]
Jg Jargonium 72 Discredited claim to discovery of hafnium. [7]
Jo Joliotium 105 Proposed name for dubnium. [8]
Ku Kurchatovium 104 Proposed name for rutherfordium. [8]
Lw Lawrencium 103 Current symbol is Lr. [6]
M Muriaticum 17 Former name of chlorine. [6]
Ma Masurium 43 Disputed claim to discovery of technetium. [7]
Md Mendelevium 97 Proposed name for berkelium. The symbol and name were later used for element 101. [6] [8]
Me Mendelevium 68 Suggested name for erbium. [6]
Ms Masrium 49 Discredited claim of discovery of indium. [7]
Mt Meitnium 91 Suggested name for protactinium. [8]
Mv Mendelevium 101 Current symbol is Md. [6]
Ng Norwegium 72 Discredited claim to discovery of hafnium. [7]
Ni Niton 86 Former name for radon. [6]
No Norium 72 Discredited claim to discovery of hafnium. [7]
Ns Nielsbohrium 105 Proposed name for dubnium. [8]
Ns Nielsbohrium 107 Proposed name for bohrium. [8]
Nt Niton 86 Suggested name for radon. [8]
Nw Newtonium 67 Suggested name for holmium. [8]
Ny Neoytterbium 70 Former name of ytterbium. [6]
Od Odinium 62 Suggested name for samarium. [8]
Pc Policium 110 Proposed name for darmstadtium. [8]
Pe Pelopium 41 Former name for niobium. [6]
Po Potassium 19 Current symbol is K. [6]
Rf Rutherfordium 106 Proposed name for seaborgium. The symbol and name were instead used for element 104. [6] [8]
Sa Samarium 62 Current symbol is Sm. [6]
So Sodium 11 Current symbol is Na. [6]
Sp Spectrium 70 Suggested name for ytterbium. [8]
St Antimony 51 Current symbol is Sb. [6]
Tn Tungsten 74 Current symbol is W. [6]
Tu Thulium 69 Current symbol is Tm. [6]
Tu Tungsten 74 Current symbol is W. [6]
Ty Tyrium 60 Suggested name for neodymium. [8]
Unb Unnilbium 102 Temporary name given to nobelium until it was permanently named by IUPAC. [9]
Une Unnilennium 109 Temporary name given to meitnerium until it was permanently named by IUPAC. [9]
Unh Unnilhexium 106 Temporary name given to seaborgium until it was permanently named by IUPAC. [9]
Uno Unniloctium 108 Temporary name given to hassium until it was permanently named by IUPAC. [9]
Unp Unnilpentium 105 Temporary name given to dubnium until it was permanently named by IUPAC. [9]
Unq Unnilquadium 104 Temporary name given to rutherfordium until it was permanently named by IUPAC. [9]
Uns Unnilseptium 107 Temporary name given to bohrium until it was permanently named by IUPAC. [9]
Unt Unniltrium 103 Temporary name given to lawrencium until it was permanently named by IUPAC. [9]
Unu Unnilunium 101 Temporary name given to mendelevium until it was permanently named by IUPAC. [9]
Uun Ununnilium 110 Temporary name given to darmstadtium until it was permanently named by IUPAC. [9]
Uuu Unununium 111 Temporary name given to roentgenium until it was permanently named by IUPAC. [9]
Vi Virginium 87 Discredited claim to discovery of francium. [7]
Vm Virginium 87 Discredited claim to discovery of francium. [7]
Yt Yttrium 39 Current symbol is Y. [6]

[edit] Pictographic symbols

The following is a list of pictographic symbols employed to symbolize elements known since ancient times (for example to the alchemists). Not included in this list are symbolic representations of substances previously called elements (such as certain rare earth mineral blends and the classical elements fire and water of ancient philosophy) which are known today to be multi-atomic. Also not included are symbolic representations currently used for elements in other languages such as the Traditional Chinese elements. Modern alphabetic notation was introduced in 1814 by Jöns Jakob Berzelius.

Chemical Symbol Name Atomic Number Origin of Symbol Why Not Used
Hydrogen 1 Daltonian symbol circa 1808. [6]
Sulfur 16 Alchemical symbol. [6]
Pallas 16 Alchemical symbol. [6]
Sulfur 16 Daltonian symbol circa 1808. [6]
⊛ Magnesium 21 Alchemical symbol. [6]
♂ Mars 26 Alchemical symbol. [6]
Stellae Fixae 29 Pre-1500s alchemical symbol. [6]
♀ Venus 29 Alchemical symbol. [6]
Copper 29 Alchemical symbol. [6]
© Copper 29 Daltonian symbol circa 1808. [6]
Arsenic 33 Alchemical symbol. [6]
Luna 48 Alchemical symbol. [6]
Iupiter 50 Alchemical symbol. [6]
♁ Antimony 51 Alchemical symbol. [6]
Antimony 51 Alchemical symbol. [6]
☾ Platinum 78 Alchemical symbol. [6]
☉ Platinum 78 Alchemical symbol. [6]
Uranus 78 Alchemical symbol. [6]
☼ Sol 79 Alchemical symbol from the 1500s [6]
Sol 79 Alchemical symbol from 1700 through 1783. [6]
[1] Pisces 80 Pre-1500s alchemical symbol. [6]
Neptunus 80 Alchemical symbol from the 1600s. [6]
Mercurius 80 Alchemical symbol from 1700 through 1783. [6]
Saturnus 82 Alchemical symbol circa 1783. [6]
Taurus 83 Alchemical symbol. [6]
  1. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj The element does not have any stable nuclides, and a value in brackets, e.g. [209], indicates the mass number of the longest-lived isotope of the element. However, three elements, Thorium, Protactinium, and Uranium, have a characteristic terrestrial isotopic composition, and thus their atomic mass given.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
  3. ^ a b c d e f g h i j k l m n o The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
  4. ^ a b c d e f g h The isotopic composition of the element can vary in commercial materials, which can cause the atomic weight to deviate significantly from the given value.
  5. ^ The atomic weight of commercial Lithium can vary between 6.939 and 6.996—analysis of the specific material is necessary to find a more accurate value.
  6. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az Name changed due to a standardization of, modernization of, or update to older previously used symbol.
  7. ^ a b c d e f g h i j k l m Name designated by discredited/disputed claimant.
  8. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Name proposed prior to discovery/creation of element or prior to official re-naming of a placeholder name.
  9. ^ a b c d e f g h i j k l m n o Temporary placeholder name.

[edit] Symbols for named isotopes

The following is a list of isotopes of elements given in the previous tables which have been designated unique symbols. By this it is meant that a comprehensive list of current systematic symbols (in the uAtom form) are not included in the list and can instead be found in the Index to isotope pages chart. Some of the following symbols are no longer in use within the scientific community, however others (most notably some of the named isotopes of hydrogen) continue to be used today. Many of these symbols were designated during the early years of radiochemistry, and several isotopes (namely those in the actinium decay family, the radium decay family, and the thorium decay family) bear placeholder names using the early naming system devised by Ernest Rutherford. Although it is not an isotope, this is perhaps the most useful place to mention that H is the proposed symbol for the only created anti-element, antihydrogen.

Chemical Symbol Name Atomic Number Origin of Symbol
Ac Actinium 89 From the Greek aktinos. Name restricted at one time to 227Ac, an isotope of actinium. This named isotope later became the official name for element 89.
AcA Actinium A 84 From actinium and A. Placeholder name given at one time to 215Po, an isotope of polonium identified in the decay chain of actinium.
AcB Actinium B 82 From actinium and B. Placeholder name given at one time to 211Pb, an isotope of lead identified in the decay chain of actinium.
AcC Actinium C 83 From actinium and C. Placeholder name given at one time to 211Bi, an isotope of bismuth identified in the decay chain of actinium.
AcC' Actinium C' 84 From actinium and C'. Placeholder name given at one time to 211Po, an isotope of polonium identified in the decay chain of actinium.
AcC" Actinium C" 81 From actinium and C". Placeholder name given at one time to 207Tl, an isotope of thallium identified in the decay chain of actinium.
AcK Actinium K 87 Name given at one time to 223Fr, an isotope of francium identified in the decay chain of actinium.
AcU Actino-Uranium 92 Name given at one time to 235U, an isotope of uranium.
AcX Actinium X 88 Name given at one time to 223Ra, an isotope of radium identified in the decay chain of actinium.
An Actinon 86 From actinium and emanation. Name given at one time to 219Rn, an isotope of radon identified in the decay chain of actinium.
D Deuterium 1 From the Greek deuteros. Name given to 2H.
Io Ionium 90 Name given at one time to 230Th, an isotope of thorium identified in the decay chain of uranium.
MsTh1 Mesothorium 1 88 Name given at one time to 228Ra, an isotope of radium.
MsTh2 Mesothorium 2 89 Name given at one time to 228Ac, an isotope of actinium.
Pa Protactinium 91 From the Greek protos and actinium. Name restricted at one time to 231Pa, an isotope of protactinium. This named isotope later became the official name for element 91.
Ra Radium 88 From the Latin radius. Name restricted at one time to 226Ra, an isotope of radium. This named isotope later became the official name for element 88.
RaA Radium A 84 From radium and A. Placeholder name given at one time to 218Po, an isotope of polonium identified in the decay chain of radium.
RaB Radium B 82 From radium and B. Placeholder name given at one time to 214Pb, an isotope of lead identified in the decay chain of radium.
RaC Radium C 83 From radium and C. Placeholder name given at one time to 214Bi, an isotope of bismuth identified in the decay chain of radium.
RaC' Radium C' 84 From radium and C'. Placeholder name given at one time to 214Po, an isotope of polonium identified in the decay chain of radium.
RaC" Radium C" 81 From radium and C". Placeholder name given at one time to 210Tl, an isotope of thallium identified in the decay chain of radium.
RaD Radium D 82 From radium and D. Placeholder name given at one time to 210Pb, an isotope of lead identified in the decay chain of radium.
RaE Radium E 83 From radium and E. Placeholder name given at one time to 210Bi, an isotope of bismuth identified in the decay chain of radium.
RaE" Radium E" 81 From radium and E". Placeholder name given at one time to 206Tl, an isotope of thallium identified in the decay chain of radium.
RaF Radium F 84 From radium and F. Placeholder name given at one time to 210Po, an isotope of polonium identified in the decay chain of radium.
RdAc Radioactinium 90 Name given at one time to 227Th, an isotope of thorium.
RdTh Radiothorium 90 Name given at one time to 228Th, an isotope of thorium.
Rn Radon 86 From radium and emanation. Name restricted at one time to 222Rn, an isotope of radon identified in the decay chain of radium. This named isotope later became the official name for element 86 in 1923.
T Tritium 1 From the Greek tritos. Name given to 3H.
Th Thorium 90 After Thor. Name restricted at one time to 232Th, an isotope of thorium. This named isotope later became the official name for element 90.
ThA Thorium A 84 From thorium and A. Placeholder name given at one time to 216Po, an isotope of polonium identified in the decay chain of thorium.
ThB Thorium B 82 From thorium and B. Placeholder name given at one time to 212Pb, an isotope of lead identified in the decay chain of thorium.
ThC Thorium C 83 From thorium and C. Placeholder name given at one time to 212Bi, an isotope of bismuth identified in the decay chain of thorium.
ThC' Thorium C' 84 From thorium and C'. Placeholder name given at one time to 212Po, an isotope of polonium identified in the decay chain of thorium.
ThC" Thorium C" 81 From thorium and C". Placeholder name given at one time to 208Tl, an isotope of thallium identified in the decay chain of thorium.
ThX Thorium X 88 Name given at one time to 224Ra, an isotope of radium identified in the decay chain of thorium.
Tn Thoron 86 From thorium and emanation. Name given at one time to 220Rn, an isotope of radon identified in the decay chain of thorium.
UI Uranium I 92 Name given at one time to 238U, an isotope of uranium.
UII Uranium II 92 Name given at one time to 234U, an isotope of uranium.
UX1 Uranium X1 90 Name given at one time to 234Th, an isotope of thorium identified in the decay chain of uranium.
UX2 Uranium X2 91 Name given at one time to 234Pa, an isotope of protactinium identified in the decay chain of uranium.
UY Uranium Y 90 Name given at one time to 231Th, an isotope of thorium identified in the decay chain of uranium.
UZ Uranium Z 91 Name given at one time to 234Pa, an isotope of protactinium identified in the decay chain of uranium.


[edit] Other symbols that look like element symbols

[edit] Notes

  1. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj The element does not have any stable nuclides, and a value in brackets, e.g. [209], indicates the mass number of the longest-lived isotope of the element. However, three elements, Thorium, Protactinium, and Uranium, have a characteristic terrestrial isotopic composition, and thus their atomic mass given.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am The isotopic composition of this element varies in some geological specimens, and the variation may exceed the uncertainty stated in the table.
  3. ^ a b c d e f g h i j k l m n o The isotopic composition varies in terrestrial material such that a more precise atomic weight can not be given.
  4. ^ a b c d e f g h The isotopic composition of the element can vary in commercial materials, which can cause the atomic weight to deviate significantly from the given value.
  5. ^ The atomic weight of commercial Lithium can vary between 6.939 and 6.996—analysis of the specific material is necessary to find a more accurate value.
  6. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az Name changed due to a standardization of, modernization of, or update to older previously used symbol.
  7. ^ a b c d e f g h i j k l m Name designated by discredited/disputed claimant.
  8. ^ a b c d e f g h i j k l m n o p q r s t u v w x y Name proposed prior to discovery/creation of element or prior to official re-naming of a placeholder name.
  9. ^ a b c d e f g h i j k l m n o Temporary placeholder name.

[edit] References

[edit] External links

v • d • e
Periodic tables

Standard · Vertical · Full names · Names and atomic masses · Text for last · Huge table · Atomic masses
Electron configurations · Metals and nonmetals · Blocks · Valences · Inline f-block · 218 elements · Alternatives

Lists of elements:
Name · Atomic symbol · Atomic number · Boiling point · Melting point · Density · Atomic mass

Groups:
1 · 2 · 3 · 4 · 5 · 6 · 7 · 8 · 9 · 10 · 11 · 12 · 13 · 14 · 15 · 16 · 17 · 18

Periods:
1 · 2 · 3 · 4 · 5 · 6 · 7 · 8

Series:
Alkalis · Alkaline earths · Lanthanides · Actinides · Transition metals
Poor metals · Metalloids · Nonmetals · Halogens · Noble gases

Blocks:
s-block · p-block · d-block · f-block · g-block

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